December 24, 2013

Expedition 38 Crew Members Take A Christmas Eve Spacewalk

Astronauts aboard the International Space Station spent part of their Christmas Eve spying on Santa from outside the orbiting laboratory.

Flight Engineers Rick Mastracchio and Mike Hopkins conducted a nearly 7-and-a-half-hour spacewalk on Tuesday to retrieve a spare pump module from an external stowage platform and install it in the currently vacated slot to restore full cooling capability for the complex. The astronauts performed a 5-hour, 28-minute spacewalk on Saturday, during which they removed the faulty pump module from the starboard truss.

On December 11, the ISS crew members encountered a problem with the pump module’s internal flow control valve, causing temperatures in the station’s cooling lines to drop. That issue forced a partial shutdown of the orbiting lab.

Mastracchio and Hopkins retrieved the spare pump module from the External Stowage Platform 3 during Tuesday’s spacewalk and installed it in the slot that is now empty through the removal of the degraded pump on Saturday.

The spacewalkers had to make five electrical connections and four fluid connections during the walk, allowing the space station to begin full dual-loop cooling again. The two men’s work will help pave the way for Commander Oleg Kotov and Flight Engineer Sergey Ryazanskiy to conduct their own spacewalk this coming Friday out of the Pirs docking compartment to install a pair of high-fidelity cameras on the Zvezda service module. The Russian cosmonauts will also be refreshing several experiment packages on the exterior of the Russian segment of the station.

Koichi Wakata, of the Japan Aerospace Exploration Agency, controlled the space station’s robotic arm, Canadarm2. Hopkins was attached to the foot restraint at the end of the 57-foot arm.

This was the second Christmas Eve spacewalk conducted in history. NASA said that 14 years ago space shuttle Discovery astronauts Steve Smith and John Grunsfeld performed an 8-hour, 8-minute spacewalk to install upgrades to the Hubble Space Telescope.

During Saturday’s spacewalk, Mastracchio’s suit faced complications during depressurization of the Quest airlock. NASA said a small amount of water entered the suit’s sublimator after the two astronauts had already hooked themselves up to airlock umbilicals. Flight controllers switched to a backup suit for Mastracchio for the next spacewalk.

Mastrachio's incident comes less than six months after another terrifying ordeal occurred with an astronaut during a spacewalk as part of Expedition 37.

European Space Agency astronaut Luca Parmitano faced a terrifying incident earlier this year when his suit began filling up with water during a spacewalk with NASA’s Chris Cassidy. Parmitano wrote on his blog about how his suit began filling up with water while he was away from the airlock, blocking his vision and closing-in on his ability to breathe.

NASA said Parmitano and Mastracchio’s incidents were unrelated and that both Rick and Mike experienced dry conditions repeatedly throughout Saturday’s activities and the two were never in danger.